1. Field of the Invention
The present invention relates to an apparatus and method of recognizing a motion, and more particularly, to an apparatus and method of recognizing a motion that is capable of performing a pointing function and a character input function using motions sensed by an optical sensor and an inertial sensor.
2. Description of the Related Art
In recent years, a technique for connecting a memory device storing, for example, pictures, music, and moving pictures to a television has been proposed to enable a user to view multimedia contents on a TV screen. In addition, an IPTV (Internet protocol television) has been developed to provide various Internet-based services and contents as well as the existing broadcasting channels to the user. Therefore, there is an increasing necessity for the use of a keyboard and a mouse, which are input units used for a personal computer (PC). For this reason, an air mouse, which is a pointing apparatus using a gyro, has come into widespread use for various apparatuses, such as a PC and a TV.
However, in order to search contents or a web page on the IPTV, a character input unit is necessarily needed. The character input unit is formed by a combination of a remote controller and a keyboard, a combination of a keypad for a mobile phone and a remote controller, or a combination of a keyboard displayed on the screen and an air mouse. The following methods can be used to input characters to a PC, not a TV: a method of forming an optical mouse into a pen shape and converting the locus of a motion on a writing pad into a character; a method of using the absolute position of a pen that moves on a special pad; and a method of recognizing the motion of a pen using ultrasonic waves and infrared rays.
When a keyboard is additionally provided in order to input characters, this structure is not suitable for a living room environment, and may hinder the posture of the user using the keyboard and user's convenient viewing. When buttons are provided in the remote controller in the form of a mobile phone keypad, the users who are not accustomed to the mobile phone keypad may have difficulty in inputting characters. When the mouse pointer is used to select a character on the keyboard displayed on the TV screen, it is difficult for a user to rapidly select a character from the keyboard displayed on the TV screen, which causes inefficiency. In the structure in which a pen-shaped optical mouse is used to convert the locus of a motion on the writing pad into a character, if a pen tip is separated from the writing pad due to inter-stroke movements, it is difficult to calculate the locus of the motion of the pen. In the structure in which a special pad is used to calculate the absolute position of a pen, a special pad is required. In the structure that recognizes the motion of a pen using ultrasonic waves and infrared rays, a distance between the pen and a motion recognizing apparatus is predetermined.
Therefore, a technique capable of providing a mouse pointing function and effectively inputting a character is demanded.